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Preview of ValueChecker

ValueChecker by akabi

Perceptually accurate value checker for artists, emulating Photoshop’s dot gain 20% profile.

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About this extension
ValueChecker is designed for artists to check and analyze value structure of images, videos, and GIFs by emulating the working gray (dot gain 20%) profile found in Photoshop or Gray Gamma 1.8 in other software.

Standard grayscale filters/modes ignore how the human eye perceives brightness, leading to inaccurate results where bright colors can appear much darker than they should. This tool utilizes Rec. 709 luminance formula within a linear RGB color space to ensure the values remain perceptually accurate.

Press Ctrl+Y to toggle the add-on or customize it to your own liking.
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Permissions and data

Required permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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Version
1.0
Size
213.72 KB
Last updated
7 days ago (Apr 19, 2026)
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License
MIT License
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